Endocrine System Part II Study Guide (no hormone chart Qs)

Question 1

difference in tissue between anterior and posterior pituitary gland

Answer 1

• Posterior Pituitary Lobe: composed of neural tissue that secretes neurohormones
  
  • Neurohypophysis: posterior lobe of the pituitary + infundibulum
• Anterior Pituitary: composed of glandular tissue; called the adenohypophysis

Question 2

Hypophyseal portal system

Answer 2

vascularly connects the anterior lobe of the pituitary to the hypothalamus
- Primary capillary plexus
- Hypophyseal portal veins
- Secondary capillary plexus
Hypothalamus regulates hormone secretion by secreting releasing and inhibiting hormones to the anterior pituitary gland

Question 3

Hypothalamic-hypophyseal tract

Answer 3

maintains neural connection to the hypothalamus, tract arises from neurons in the paraventricular and supraoptic nuclei and runs through the infundibulum
- Secretes 2 neurohormones – oxytocin and ADH
- Paraventricular neurons produce oxytocin
- Supraoptic neurons produce ADH
Hormones are stored in axon terminals; they are released into the blood when neurons fire

Question 4

tropic hormone

Answer 4

regulate the secretion of other hormones

Question 5

hormone that stimulates the release of GH

Answer 5

Growth hormone releasing hormone (GHRH) stimulates GH – it’s also stimulated by ghrelin

Question 6

hormone that inhibits GH release

Answer 6

GHIH - growth hormone inhibiting hormone

Question 7

hormone that stimulates the release of TSH (thyroid stimulating hormone)

Answer 7

thyrotropin releasing hormone (TRH)

Question 8

how is TSH release inhibited?

Answer 8

by rising blood levels of thyroid hormones acting on both the pituitary and the hypothalamus; also inhibited by GHIH

Question 9

hormone that stimulates the release of ACTH

Answer 9

hypothalamus corticotropin releasing hormone (CRH)

Question 10

How is the release of ACTH inhibited?

Answer 10

Rising levels of corticosteroids feed back and block the secretion of CRH

Question 11

How is the release of FSH and LH inhibited?

Answer 11

via feedback of the gonadal hormones

Question 11

hormone that stimulates the release of FSH and LH

Answer 11

gonadotropin releasing hormone (GnRH)

Question 12

In females, levels of prolactin tend to rise/fall in rhythm with _________.

Answer 12

estrogen

Question 12

thyroid gland location

Answer 12

anterior neck, located on the trachea, just inferior to the larynx

Question 13

2 forms of thyroid hormone that the thyroid gland secretes

Answer 13

• Thyroxine (T4): major form; consists of 2 tyrosine molecules with 4 bound iodine atoms
• Triiodothyronine (T3): form of TH that has 2 tyrosine molecules with 3 bound iodine atoms

Question 14

parathyroid gland location

Answer 14

Embedded in the posterior aspect of the thyroid

Question 15

adrenal glands location

Answer 15

atop the kidneys

Question 16

Adrenal Medulla

Answer 16

nervous tissue – part of the sympathetic nervous system – secretes catecholamines

Question 16

adrenal cortex

Answer 16

3 layers of glandular tissue – synthesize and secrete several different hormones
- The adrenal cortex produces over 24 different hormones known collectively as corticosteroids

Question 17

Addison’s disease

Answer 17

not enough acth is produced from pituitary gland -> not enough cortisol
- weight loss
- fatigue + darkened skin

Question 18

Cushing’s Disease

Answer 18

too much acth is produced from pituitary gland, causing there to be too much cortisol released from adrenal glands
- weight gain
- red and fragile skin

Question 19

cells of the pancreas that secrete glucagon

Answer 19

alpha cells

Question 20

cells of the pancreas that secrete insulin

Answer 20

beta cells

Question 21

pancreas’ acinar cells

Answer 21

exocrine cells that produce enzyme-rish juice needed for digestion